The Nexi XPay Build WordPress plugin through 7.6.2 does not verify the payment result supplied to several of its unauthenticated routes, allowing attackers to mark arbitrary orders as paid or failed, to cancel them, and to obtain order keys which expose guest buyers' details.

The Nexi XPay Build WordPress plugin through 7.6.2 does not correctly validate the security token on its payment notification route, accepting the request when the target order has no stored token, which allows unauthenticated attackers to mark arbitrary orders as paid, or to mark genuinely paid orders as failed.

The Nexi XPay Build WordPress plugin from 7.6.1 to 7.6.2 does not verify that the saved payment token being requested belongs to the current user, allowing unauthenticated attackers to retrieve other customers' stored card token references together with a valid authorisation signature.